BRUNSWICK, Maine — It was a raw, damp afternoon for a look at a new bird.

Still, more than 125 people strolled through Kestrel Aeroworks’s design, testing and manufacturing facility at Brunswick Executive Airport during the fledgling aircraft company’s open house Monday.

Most of the prospective buyers and curious aviation buffs took guided tours, sat in a production mock-up fuselage, munched appetizers and sipped drinks while talking prop-shop.

Pat Andrews was one of a group that braved the cold coastal rain to drive from Rye, N.H., to get a look at Kestrel’s new plane.

The proof-of-concept design has no name or working model designation yet. But when it starts its first take-off roll sometime in 2015 — “Hopefully, it’ll be 2015,” said Kestrel’s co-founder, Adrian Norris — the company expects to have a solid waiting list.

Andrews hopes so, too. He currently flies a Cirrus SR22, a small, single-engine four-seater he keeps tied down at Pease Tradeport.

He liked the look of the new, nameless Kestrel.

Cirrus Aircraft was founded in 1984 by brothers Alan and Dale Klapmeier.

The Cirrus was unique for its time because it used a combination of composite materials for its cabin and traditional aluminum for its airframe and control surfaces.

Twenty-five years later, Alan Klapmeier joined the evolving Kestrel project and brought with him the idea for using laminated composites in virtually every significant piece of the aircraft, including its structural and wing spars, skin, even the turbo-prop engine’s air intake.

Kestrel’s prototype airplane, tail number N352F, is the working model from which its designers learned what they would do differently with the new model. Built starting in 2004 and first flown in 2006, it has spent 450 hours aloft, including two trans-Atlantic crossings.

“It doesn’t spend much time in the air now,” Norris said. “We’ve learned what we needed to learn from it.”

Among the refinements, the next-generation plane will have a different engine, longer range, better performance specifications and cargo capacity, and larger windows. It will be sleeker, yet with a wider, roomier cabin.

The cockpit, too, is designed to be “wider and easier for aging, pie-eating pilots to get into,” Norris added, patting his belly.

Additionally, the new Kestrel will have a Cirrus Aircraft carryover feature — an emergency parachute mounted behind the engine that will deploy in case catastrophe occurs.

The idea is that, while a parachute landing might crumple the plane itself, the passengers and pilots likely would survive to fly again.

On Monday, groups of eight or 10 people wound through the hangar, stopping in each department for a brief lesson in airplane construction.

Tours started in the equipment and furnishings department, where Todd Hurley explained that his team designed “everything that you can see or touch,” such as avionics controls, lighting, seats, interior cabin fabric and trim.

A foam-and-lumber contraption stood nearby, the embryonic engineering platform for the new plane’s seats.

“Eventually, I’ll get to strap a crash-test dummy into it and send it down the track,” Hurley said. “That’s actually one of the favorite parts of my job.”

Waterville native Mike Leighton works in mechanical systems, otherwise known as “everything that leaks or squeaks.”

All the departments have pithy names like that.

Landing gear is Leighton’s baby: He’s designing it with larger tires that carry lower air pressure, so the plane can take off or touch down from grass, gravel or tarmac runways.

Despite the frightful weather outside, the environment inside was congratulatory. Congressional delegates milled about, administrators from the Midcoast Regional Redevelopment Authority and state commissioners joked about the two- or four-wheeled toys that they’d like to have.

But a spectre of unrest hovered over the Brunswick plant, which currently is at the center of of a tax dispute between the town and MRRA.

Kestrel dealt a blow to MRRA earlier this year when the bulk of its 600 prospective manufacturing jobs were moved to Superior, Wis., when Maine couldn’t — or wouldn’t — match a deal offered by that state’s department of economic development. However, 39 people currently work in Brunswick — and will for the remainder of Kestrel’s 20-year lease with Brunswick Landing and MRRA. As many as 10 more employees are expected to be hired when production of parts for the new plane ramps up in 2013.

Additionally, Kestrel’s innovative use of composite materials to form its fuselage, airframe and internal load-bearing structures means the company needs workers with experience in modern laminates.

Several of its technicians in the manufacturing and production department also are students in the composites engineering program at Southern Maine Community College, just a few blocks away.